Organic light-emitting devices are a type of light-emitting device that includes a thin film containing a fluorescent organic compound interposed between an anode and a cathode. When electrons and holes are injected from the respective electrodes, excitons of the fluorescent compound are generated and the organic light-emitting device emits light as the excitons return to their ground state.
The recent advancement of organic light-emitting devices has been remarkable. Organic light-emitting devices have made it possible to produce thin and light-weight light-emitting devices that have high luminance at a low application voltage and a wide variety of emission wavelengths and display rapid response. This suggests that the organic light-emitting devices can be used in a wide variety of usages.
However, presently, there remains room for improvements. To be more specific, emitted light needs to have a higher luminance and the optical conversion efficiency needs to be increased for practical applications. Moreover, improvements are needed in terms of durability, such as changes with time caused by long use and deterioration caused by oxygen-containing atmospheric gas and humidity. In order for organic light-emitting devices to be used in full color displays and the like, one of the characteristics required of the organic light-emitting devices is that blue light is emitted at a high color purity and high efficiency. However, this has not been satisfactorily achieved. Accordingly, organic light-emitting devices that exhibit high color purity, emission efficiency, and durability and the materials that can be used to make such devices are in demand.
Various compounds and organic light-emitting devices using the compounds have been proposed to address the challenges described above. For example, PTL 1 to PTL 4 propose organic compounds having fluoranthene and benzofluoranthene backbones and organic light-emitting devices that use such organic compounds. However, their emission hue, emission efficiency, luminance, and durability need to be improved further.
NPL 1 proposes an organic compound having a 4,10-diazachrysene backbone and a synthetic method therefor.